1. Field of the Invention
This invention relates generally to the field of microbicides. In particular, it relates to a stable microbicide having anticorrosive properties comprising a mixture of hydrogen peroxide, peracetic acid, acetic acid and purified water which is substantially free of contaminants or stabilizing and sequestrant type additives.
2. Description of the Related Art
Peracetic acid/peroxide containing compositions have a long history of use as disinfectants and sterilizers due to their microbicidal activities. However, peroxide containing compositions are high-energy-state compounds and as such can be considered thermodynamically unstable. Therefore, because there is a strong tendency for these compositions to decompose in the presence of multivalent metal ions, stabilizers are added. Stabilizers may be agents such as sodium pyrophosphate, phosphonic acid or chelating agents such as 8-hydroxyquinoline. Stabilizers act by removing trace metals which accelerate the decomposition of peroxides. Stabilizers also accelerate the reaction between hydrogen peroxide and acetic acid to form peracetic acid. Therefore, for any given concentration of hydrogen proxide and acetic acid, the addition of a stabilizer increases the concentration at equilibrium of peracetic acid.
While conventional art compositions are stable due to the use of added stabilizers, they are also highly corrosive to the very metals they are designed to disinfect namely surgical and dental instruments made of aluminum or brass, which instruments are often plated with an ornamental or protective layer of nickel or nickel and/or chromium. Additionally, certain susceptible individuals often exhibit allergic reactions to the conventional art formulations. Further, after prolonged use these conventional art formulations often leave mineral-like deposits on the metal instruments they sterilize.
A concentrated composition that contains no stabilizer or sequestrant type additives that is both stable during storage for prolonged periods of time and possesses anticorrosive properties would be a decided advantage over these conventional formulations. Further, a use-dilution formulation that may be reused several times, is stable for relatively long periods in the diluted form and possesses anticorrosive properties would be a further advantage over conventional formulations.